Multimodality in galaxy clusters from SDSS DR8: substructure and velocity distribution M. Einasto, J. Vennik, P. Nurmi, E. Tempel, A. Ahvensalmi, E. Tago, L. J. Liivamägi, E. Saar, P. Heinämäki, J. Einasto and V. J. Martínez A&A, 540 (2012) A123 Published online: 09 April 2012 DOI: 10.1051/0004-6361/201118697